I've noticed that the oil brush behaviour can be in-consistent for me.

On some occasions it will lay down new colour on top of existing and on other occasions it will blend or smudge the existing colour. Am I missing something connected with amount of paint depth on the canvas and/or the paint being wet or dry?

I can't find a way to dry the paint on the canvas other than painting with the instant dry setting on the brush.

Any help/advice is appreciated.

Chris